I don't believe that we have seen a breakdown of the £60 million cost, to know how much is filling in the void under the tracks, and how much is the polluted water. Indeed there is a continued lack of clarity as to where the polluted water is actually originating from. Ultimately that water will still flow from wherever it is originating from, so has to be diverted long term. That diversion could be achieved without the tunnel being re-opened. If it is not diverted then we will be back in the same scenario in a few years time of water undermining the track (polluted or clean water).
It is striking how a significant part of the commuter traffic to Sellafield has melted away in spite of the special Rail Replacement Buses all the way to Sellafield which are being provided.
Traffic which is now going by road (private car or the Stagecoach works buses). With what will become a nearly 3 year closure that traffic is not going to return to the railway. But even before closure the peak commuter traffic was down, partly due to changing shift patterns, and partly down to long term unreliability arising from the latent disputes leading to far too many short notice cancellations.
Personally I have changed how I do journeys, using Corkickle far more than I used to or need to, specifically to count in the statistics for bus use, in case the shuttle bus service is deemed to be underused, and ultimately cancelled.